Let-off mechanism for looms.



J. NORTHROP. LET-OFF MECHANISM FOR LOOMS.

APPLICATION FILED MAY, 1909.

J. NOR-THROP. LET-OFF MEGHANISM FOR LOOMS. PPLIOATION FILED Mns. 190e.

Patented Nov. 30, 1909 2 SHEETS-SHEET Z N 4ururnn 4sfratrns ,PATENTonnicn.

I JONAS NOIRJLIHIIROP,y Fl HOPEDALE, MASSACIHUSE'TS,l ASSXGNOR T0WILLIAM T.

DRAPER, 0F HOPEDALE, MASSACHUSETTS. y

LET-OFF MECHANISM FOR LOOMS.

i Specification of Letters Patent. Patented NOV. 30. 1909.

Application filed May 5, 1969. Serial No. 494,171.

vdrawmgs representing hke parts.

The lnvention to be hereinafter described v*relates to let-offmechanisms for looms 'of the friction let-off type. -v

The present invention is a developmentV from the let-off'mechanismshown, described, and claimed in my prior patent, No. 912,722,l4`ebruary'16, 1909. In said prior'patent means were disclosed wherebytheweight of the Warp beamdetermined the amount of -frictionalresistance such beam would offer to the withdrawal of the warp threads,

' effective in counteracting any lifting H.warp threads.

and whereby the tension or pull of the warp threads in unwinding thebeam was made tendency of the said beam due to the pull of the As oneform of means for carrying the said invention into effect, the

whip roll support was made to rest upon" the journals of thewarpbeam. 4In such event, however, not vonly did'the tension of the warp threadsre-actupon the journals of the warp beam to prevent lifting movementthereof, but the weight of the Whip roll and its support did the same,and incideutally added tothe weight of the warp beam and its load.

The present invention aims toyieldingly sustain the whiproll and supportof said prior structure, so that the warpibeiam is normally free fromsuch Weight, andryet to permit the whip roll support to yield and restupon the journals of the warp `beam when tension is placed upon theWarp.'

'.lhe invention will best be understood from thc following descriptionand accompanying drawings disclosing one form of means for carrying theinventioninto effect. In the drawings, Figure 1 is a side view ofsufficient of a loom and let-off mechanism to'illustrate the associationof the present ."invention therewith; Fig. 2 is a. rearelevation'showing one end of thel beam and its associated parts; Fig. 31s a. sectlon on line bolt 61, and the opposite end of sai 3-3, Fig. 1;and F'g. 4 is a section' on line 4--4, Fig. 2.

The loom -frame 1, the bracket 2 provided with the seat 4 to receive thejournal of the warp beam when occasion requires,

the cam head 36 having the seat 37, handle 38, the guide 8 for the leg 9of the bearing 10, the end 11 of the leg 9, resting on the toothed edge1.3"oft-he lever 14, the bracket l5 for supporting said lever 14, the.warp beam 29 having a head 30, journal 31, friction pulley 34, frictionmember or chain, stirrup' 35, the guide orv whip roll 40 over which thewarp threads pass, the' whip roll support 44 havlng-the slot 45 and. adjustably connected to the depending arm 48 by the bolt-and nut 46 and 47,and guided 1n its vertical movement by the slot 50 formedin the loomvframe, and the toe 49 disposed above the journal of warp beam, `vmayallA be substantially as indicated in my prorpatent mentioned orvotherwise as described.

In the said patent the toe 49, during such times as the whip rollsupport 44 was in coacting relation with the journals of the warp beam,rested upon said journals. In

the present invention, however, the whip roll support is yieldinglysustained so as to maintain the toe 49 some distance above the journal8l of the warp beam, the general construction being such that whentension is placed upon the warp thread, as during the formation ofthe-shed, the whip roll support will be depressed against lts yieldingsustaining means so that 'the toc 49 will then come in contact with the4journalot' the warp beam, and when the strain or tension of the Warpthread `is relieved, as by .closing the shed,` the yielding sustainingneans'for the whip roll'support will raise the same, thus actlng as athin place pre-g' Venter. As one means for carrying this feature of theinvention into effect, the whip roll support, 48, is provide with aprojection 60A through referably the depending armwhich isscrew-threadedan 'adjusting bolt 61, Fi s. 3 and 4, provided with a 'lock nut' 62 an aturning head 63.

Secured or projecting from ,the loom frame lbelow the projection 60 is alug 4or bracket' 64, and interposed between the projection 60and bracketor lug 64 .is thesus.- tainin means orspring 65, the upper end `of whichengages the seat of a cap 66 bearing against the end of the adjustilgscrew t spring preferably embraces a lng' or nipple 67. The

construction and general disposition of the parts is such that when theWarp thread 4l is not under tension the spring G5 will sustain the Whiproll support and whip roll so that the toe 49 will be disposed somedistance above the journal 31 of the Warp beam, but When tension isplaced upon the Warp threads, as hereinbefore pointed out, the

Whip roll and whip roll support will be depressed to carry thetoe 49into contact with the journal 3l of the Warp beam, and when the tensionis released on the Warp threads, the spring 65 will raise the Whip rolland Whip roll support thus causing this characteristic action of theWhip roll to operate as a thin place preventer, as will readilyunderstood by those skilled in the art.

In the above described construction, it'

will be understood that the drawings show and the description isdirected to devices at one end of the warp beam, those at the other endbeing a duplicate and, consequently, unnecessary to specificallydescribe. It will also be obvious that the sustaining means or spring 65acts as a counterbalance for the Whip roll and Whip roll support, andthat changes and variations may be made in the detailsof structureWithout departing from the true scope of the present invention which isdefinitely set forth in the claims.

What is claimed is:

l. In a loom, the combination of a Warp beain,' a friction let-offgoverned by the Weight of the Warp beam effective thereon, means actingunder warp tension to mailiy tain the weight of the warp beam effectiveon the friction let-off under variation of warp tension, and balancingdevices for said means.

2. In a loom, the combination of a Warp beam, a friction let-offgoverned by the Weight of the warp beam effective thereon,

a guide over which the warp threads pass from the Warp beam, meansconnected to said guide and acting under Warp tension to maintain theweight of the Warp beam effective on the friction let oif undervariations of'v'varp tension, and yielding supporting devices for-saidmeans.

.3. In a loom, the combination of a Warp beam,a friction let-offdepending for the degree -`of its effective action upon the Weight ofthe Warp beam, means reacting under tension of the Warp threads forpreventing decrease in etectve Weight of the Warp. beam upon thefriction let-off due to Warp tension, and a yielding support for saidmeans.

4. In a loom, the combination of a Warp beam, movable bearings therefor,a friction device connected to said movable bearings to govern theletoff by the Weight of the Warp beam, means controlled by the tensionof the warp threads for preventingmovement of said bearings due to Warptension, and a yielding support for said means acting under the varyingtension of the Warp threads to move said means.

5. In a loom, the combination of a Warp beam, movable'bearings therefor,a friction device connected to said bearings to govern the let-olf bytheweight of the Warp beam, and a yieldingly mounted thin place preventeracting under Warp tension to maintain the weight of the Warp beameffective on .the friction let-off under varying condi- -tioiisof warptension.

6. In a loom, the combination of a Warp beam, movable bearinvs therefor,a friction device connected to said bearings to govern the let-off bythe weight of the Warp beam, a whip roll, a whip-roll support having apart acting under Warp tension to maintain the Weight of the warp beameffective on the friction let-of, and yielding'means permitting the Whiproll to yield under tension of the Warp threads.

7. In a let-of mechanism for looms, the I JONAS NORTHROP.

Witnesses IA'rinoii J. OCONNELL, VVnNniiLL rima/ins.

